package cn.tedu.v6;

import java.io.*;
import java.net.*;
import java.util.*;

/**
 *Version 6 exit退出和在线用户列表
 */
public class Server {
    private ServerSocket serverSocket;
    private static final Integer PORT = 1111;
    private List<PrintWriter> allOut = new ArrayList<>();
    //1.私有化集合保存所有用户名--OnlineUsers
    private Set<String> OnlineUsers=new HashSet<>();
    private Map<String, String> userDataBase;

    public Server() {
        try {
            serverSocket = new ServerSocket(PORT);
            userDataBase = new HashMap<>();
            userDataBase.put("rh", "123456");
            userDataBase.put("zrh", "654321");
        } catch (BindException e) {
            System.out.println("端口号重复创建");
        } catch (IOException e) {
            System.out.println("申请端口号失败");
        }
    }

    public void start() {
        try {
            while (true) {
                System.out.println("----等待客户端链接----");
                Socket socket = serverSocket.accept();
                String ip = socket.getInetAddress().getHostAddress();
                System.out.println(ip+"一个客户端链接成功了");
                new Thread(new ClientHandler(socket)).start();
            }
        } catch (IOException e) {
            System.out.println("服务器端通讯断开了");
        } finally {
            if (serverSocket != null && !serverSocket.isClosed()) {
                try {
                    serverSocket.close();
                } catch (IOException e) {
                    System.out.println("服务器关闭失败");
                }
            }
        }
    }

    public static void main(String[] args) {
        new Server().start();
    }

    private synchronized void broadcastMessage(String message) {
        for (PrintWriter pw : allOut) {
            pw.println("消息广播" + message);
        }
    }

    //2.封装方法：同步转发给所有客户端消息：“在线用户：“+onlineUsers
    //updateOlineUsers 更新在线名单的方法：”在线用户：“+onlineUsers
    //字符串：String userList=”在线用户“+String.join("、",onlineUsers)
    private synchronized void updateOnlineUsers(String message){
        String userList="在线用户"+String.join("zrh",OnlineUsers);
        for(PrintWriter pw:allOut){
            pw.println(userList);
        }
    }

    private class ClientHandler implements Runnable{
        private Socket socket;
        private String ip;
        private BufferedReader br;
        private PrintWriter pw;
        private String username;
        private String password;

        public ClientHandler(Socket s){
            this.socket=s;
            ip=socket.getInetAddress().getHostAddress();
            try {
                br= new BufferedReader(new InputStreamReader(socket.getInputStream()));
                pw=new PrintWriter(new BufferedWriter(new OutputStreamWriter(socket.getOutputStream(),"UTF8")),true);
                 synchronized (allOut) {
                    allOut.add(pw);
                }
            } catch (IOException e) {
                System.out.println("客户端断开通讯");
            }
        }
        private boolean Login(String user,String pass){
            return userDataBase.containsKey(user)&&userDataBase.get(user).equals(pass);
        }
        private void handlerChat(){
            new Thread(()->{
                try {
                    String message;
                    while((message= br.readLine())!=null){
                        System.out.println("客户端说："+message);
                        System.out.println("服务器请输入");
                        if (message.equalsIgnoreCase("exit")){
                            //输入exit，关闭链接
                            pw.println("exit");//打印
                            System.out.println(username+"客户端退出"+"ip"+"退出聊天室");
                            break;//中断
                        }
                        broadcastMessage(message);
                    }
                } catch (IOException e) {
                    System.out.println("客户端读入失败");
                }
            }).start();
            Scanner input=new Scanner(System.in);
            while (true) {
                System.out.println("服务器请输入");
                String say=input.nextLine();
                pw.println("服务器说："+say);
            }
        }
        public void run() {
            try {
                pw.println("请输入用户名：");
                pw.println("请输入密码：");
                password=br.readLine();
                if(Login(username,password)){
                    pw.println("登录成功，欢迎进入聊天室");
                    //3.所有用户添加至集合中【同步块：登录集合】
                    //3.1 转发在线用户方法
                    synchronized (OnlineUsers){
                        OnlineUsers.add(username);
                        updateOnlineUsers(username);
                    }
                    handlerChat();
                }else{
                    pw.println("登录失败，用户名或者密码错误");
                    socket.close();
                }
            } catch (NullPointerException e) {
                System.out.println("IO流传入对象,有对象为Null，立马核对，建议try块中对象可能赋值为null");
            } catch (IOException e){
                System.out.println("服务器端断开链接");
            } finally {
                //4.客户端断开连接，移除当前集合【同步】
                synchronized (OnlineUsers){
                    System.out.println(username+"退出聊天室");
                    if(OnlineUsers.contains(username)){
                        try{
                            OnlineUsers.remove(username);
                        }catch(Exception e){
                            e.printStackTrace();
                        }
                    }
                }
                allOut.remove(pw);
                synchronized (allOut) {
                    allOut.remove(pw);
                }

                if (br != null)
                    try {
                        br.close();
                    } catch (IOException e) {
                        System.out.println("通讯结束：关闭失败");
                    }
                if(pw!=null) pw.close();
                if (socket != null&&socket.isClosed())
                    try {
                        socket.close();
                    } catch (IOException e) {
                        System.out.println("通讯关闭失败");
                    }
            }
        }
    }
}
